48 On Vegetable and Animal Analysis, 
this last acid, the caustic alkaline solutions reduce it to 
the colour of carburet of iron: the characters of the 
writing nevertheless remain without alteration, and it 
cannot pass through these different states except after long 
macerations. The principles of which it is composed ren- 
der it incorruptible, and it can retain its properties many 
years.” 
The results which we obtained, coincided entirely with 
those of the author, and we have no hesitation in saying, 
that his is the best we have ever seen of the kind which 
is called indelible ink. It is liable, however, to deposit 
a sediment, a disadvantage which we think might be re- 
moved by M. Tarry after a few more experiments. We 
have tried to discharge it with all the known chemical 
agents, hut without effect ; and we think the inventor de- 
serves the thanks of the Institute, and of the community at 
large. ^ 
, * It may, perhaps, be acceptable to our readers to have Dr. Lewis’s receipt 
given in this place. His observations are to be found at large in the Commerce 
of Arts. 
“Put into a stone or glass bottle, or any other vessel, three ounces of finely 
powdered galls, one ounce of green vitriol, one ounce of logwood, finely rasped 
or bruised, one ounce of gum arabic, and a quart of soft water. Shake the bot* 
tie well, and let the ingredients stand in a moderately warm place for a week or 
ten days, shaking it frequently in the day. It is then fit for use ; but a little be- 
fore it is put into the ink-stand, it is better to shake the bottle that the colour may 
be more uniformly difiused.’’ 
I have tried this and various other receipts for ink ; but after an experience of 
several years, I prefer the following, by Mr. Ribancourt, from Ghem. Anaal. 
vol. ii. 
“ Eight ounces of galls, and four ounces of logwood, are boiled with tVelve 
pounds of water for an hour, or till one half of its quantity's evaporated. This 
liquor is then fjefcolated through a hah* sieve, and four ounces of vitriol, or sul- 
phate of iron, three ounces of gum arabic, one ounce of copperas or sulphate of 
copper, (so in the copy,) and one ounce of sugar candy, are added. The whole 
mass is stirred to promote the solution of the salts and gum, after which it 
is left to stand for twenty -four hours. The liquid is then poured oft" from its 
coarse sediment, and preserved in well stopped glass or stone jars. This ink ac- 
quires a beautiful black colour, which it retains for a long time.” 
It is to be regretted that Mr. Tarry has not given us the receipt for his ink, 
which such celebrated chemists as the authors of the above report, speak so 
highly of. Editor. 
